The Global Battle Against Measles is Losing Ground

This month, a British child succumbed to measles, and in June, a Canadian infant lost their life to the same disease. Additionally, two American children have died from measles this year. This situation is tragic considering measles is preventable, yet we are witnessing a regression in public health behavior. If we do not take appropriate action, we may see a resurgence of other vaccine-preventable diseases.

The United States is currently grappling with its largest measles outbreak since the disease was declared eliminated in 2000, with 1300 confirmed cases, marking the highest incidence in 33 years. Europe is not exempt; in 2024, it reported its worst outbreak in over 25 years, more than doubling the cases from the previous year. Last year alone, the UK recorded nearly 3000 confirmed cases, the highest since 2012. Meanwhile, Canada saw a rise in measles cases, reporting over 3,800 cases this year, a total not seen in the past 26 years.

This unprecedented situation mirrors a time when many countries experienced major outbreaks in the 1980s and 90s, largely due to a single-dose vaccination policy for measles, mumps, and rubella (MMR). Implementing a two-dose program proved to be about 97% effective in preventing measles, leading to a significant decline in cases, and many nations had proclaimed the elimination of measles by the early 2000s.

This current crisis is astonishing. The resurgence of measles is not due to ignorance on how to prevent it but a lack of effort in vaccination campaigns. “We have never before seen measles spread this way, primarily driven by vaccine hesitancy,” says Tinatan from Northwestern University, Illinois. “This is particularly disheartening given the availability of a safe and effective vaccine.”

Herd immunity against measles occurs when over 95% of the population is vaccinated. This threshold was achieved in American kindergarteners with a two-dose regimen during the 2019-2020 school year, but by four years later, coverage dipped below 93%.

However, national averages can obscure the reality on the ground. Vaccination rates began to decline in many US counties prior to 2019. In fact, Peter Hotez from Baylor College of Medicine raised concerns about the declining vaccination rates in Gaines County, Texas—epicenter of the current outbreak—as early as 2016. Since then, coverage has deteriorated dramatically, from around 95% to under 77%. “We’ve been anticipating this situation for at least a decade,” Hotez states. “To understand the crisis, one must look at local vaccination rates, revealing pockets with alarmingly low coverage.”

Similar trends are evident globally. In Canada, vaccination rates for children aged two holding at least one MMR dose plummeted from nearly 90% in 2019 to below 83% in 2023. Alberta, a hotspot in the current outbreak, reported percentages dropping from over 83% in 2019 to approximately 80% in 2024, with some communities as low as 32%.

Meanwhile, the UK has seen less than 85% of five-year-old children receive both MMR doses between 2023 and 2024. Out of the 48 OECD member countries, the UK ranks 30th in measles vaccination rates with Canada at 39th, New Zealand at 32nd, and the US at 4th. Hungary leads with close to 100% coverage, while Romania lags behind at around 20%.

The rise in vaccine hesitancy significantly contributes to this decline, with prominent figures like Robert F. Kennedy Jr. leading the charge against vaccination, making unfounded claims that equate the risks of the MMR vaccine with measles, which can include encephalitis and blindness. The risks tied to measles infections remain significant—about 1 in 1000 individuals contracting measles develops encephalitis, compared to 1 in 1 million vaccinated children.

Despite his stance, Kennedy encourages vaccinations. During a Fox News interview in March, he mentioned that the US government is committed to ensuring vaccines are accessible.

However, this may be too little, too late. While measles incidents seem to be decreasing in the US, Hotez warns of a potential spike in cases when children return to school. The ongoing outbreak, now in its seventh month, risks jeopardizing the US’s measles elimination status. The UK has already faced similar challenges, losing its status two years after eradicating measles in 2016, before finally regaining it in 2023.

Hotez expresses concern that the current measles outbreak may be just the beginning and that increasing vaccine refusals could hinder progress against other preventable diseases, such as polio and pertussis. “I fear this won’t stop with measles,” he warns.